U.S. Pat. No. 4,251,841 discloses a magnetic head slider of a ceramic material comprising substantially 70% Al.sub.2 O.sub.3 and 30% TiC. This material is rather easy to process, is resistant to fracture, has high abrasion qualities, and a long lifetime, and is electrically conductive.
As the data density per surface unit of magnetic storage disks increases, it is necessary to reduce the distance between the magnetic head and disk surface, thus reducing the air cushion between the slider carrying the magnetic head, and disk surface. This increases the frequency and likelihood of the slider undesirably impacting the disk during its movement relative to the record carrier. To avoid collisions between head and disk and consequent damage to both, or at least to decrease the defects thus caused, as well as to improve the conditions upon start and stop, it is known to apply a lubricant on the disk. Actual use revealed the fact that a too thin lubricant film cannot reliably prevent the damaging of the disk upon contact with the head, whereas a too thick lubricant film has the effect that at the beginning of the relative movement between disk and head, i.e. upon starting, the magnetic head slider sticks to the disk. Upon starting, the slider may therefore to torn off its arm, or the arm may become bent, or there may be further damage. To apply a lubricant film in precisely the correct thickness, and to keep it at that thickness is very complicated and in actual use very difficult to consistently reproduce. On the other hand, investigations have shown that the surface of the magnetic head slider opposite the disk surface considerably influences the behavior with respect to the contact between head and disk.